Jérôme,
Once you've set up an individual patch (using 1 or 2 DCOs), you can then use 2 different patches together in Tone Mix mode (but at reduced polyphony).
In Operation Memory mode,
you can mix up to 8 patches (or split up 8-note polyphony as desired,
e.g. ch1=4 notes, ch2=2 notes, ch3=1 note, ch4=1 note).Once you've set up an individual patch (using 1 or 2 DCOs), you can then use 2 different patches together in Tone Mix mode (but at reduced polyphony).
Regards,
JPS